"Markus Kayser’s Solar Sinter Project takes the desert’s two most abundant resources, sunlight and sand and puts them to work manufacturing glass objects. Kayser loads the sand into a solar-powered 3-D printer where it serves as the raw material for glass.

In a process that’s fascinating to watch, concentrated sunlight replaces the laser typically found in 3D printers, melting sand (instead of resin) in patterns to form an abstract sculpture or, more usefully, a bowl."

I think this type of machine - scaled down, marrying robotic technology with human oversight - is just the sort of thing the first humans on Mars need to bring with them. Although the amount of solar radiation available on Mars is nowhere the intensity of the Sahara, reflectors could be used to concentrate the solar power and achieve furnace-like temperatures. The production of the bowl at the end of the video shows that useful objects can be produced.

Of course, I am not suggesting that the Mars pioneers would take exactly this type of machine, but it shows that small scale smelting could take place and that a variety of objects to be used in the kitchen, in farm areas, or in exploration could be produced.

I think on Mars the pioneers would probably take with them small furnaces to use in conjunction with solar power.